nothing-without-science:

The story behind DNA’s double helix

The notorious race to uncover the structure of DNA, the molecule of inheritance, began in 1951, when American biologist James Watson  arrived at the University of Cambridge. Here he met Francis Crick, an English physicist and the two began building scale models to test their ideas of what DNA’s appearance might be.

Meanwhile, two scientists at King’s College London called Maurice Wilkins  and Rosalind Franklin were also studying DNA. They were attempting to crystallise the molecule to make an x-ray pattern of it. They hoped this would provide important clues about its structure.

Although the two institutions were effectively competing against each other, Francis Crick (University of Cambridge) and Maurice Wilkins (King’s College London) communicated regularly. Letters sent from Wilkins to Crick reveal their close personal relationship.

It was Rosalind Franklin’s famous x-ray image, nicknamed ‘Photo 51’, that finally revealed the structure of DNA in May 1952. The pattern appeared to contain ‘rungs’, like those on a ladder, set between two strands. The fuzzy “X” pattern indicated DNA’s helix shape. In early 1953, Wilkins showed Watson the image, seemingly without Franklin’s knowledge.

Full story here

(via biomedicalephemera)